Expansion-bit.



v110.890,493. PATENTEDJUNEQ,1908.

c. A.BU'TLER.

EXPANSION BIT.

.APPLICATION FILED SEPTA. 1907.

I n I w/TNESS s CHARLES AUGUSTUS BUTLER, OF BARTLESVILLE, OKLAHOMA.

EXPANSION BIT.

Specification of Letters Patent.

'Patented June e, i908.

Application filed September 4, 1907. Serial No. 391,334.

To all whom it may concern:

Be it known that I, CHARLES A; BUTLER, a citizen of the United States,and a resident of Bartlesville, District 27, Oklahoma, have invented newand useful Improvements in Expansion-Bits, of which the following is afull, clear, and eXact description.

This invention has reference to improvements in expansion bits moreespecially designed for the drilling of oil and Artesian wells, and hasfor its object primaril)T to provide a bit which is adapted to drill ahole of sufficient diameter at a single operation for receiving the Wellcasing, and permit of the said casing being inserted in the hole as thdrilling operation proceeds,

Tt is necessarjT in drilling wells through loose formations to sink thecasing at the time of drilling in order to support the walls of the holeand prevent the earth from caving in. This has heretoforebeen done byfirst drilling a hole of substantially the internal diameter of thecasing and thereafter enlarging the hole as the casing is sunk, with atool known as an under reamer. lith my invention the drilling isaccomplished with less labor, and the time required for the work iscorrespondingly diminished.

Reference is to be had to the accompanying drawings forming a part ofthis specification, in which similar characters of reference indicatecorresponding parts in all the views.

Figure 1 is a side elevation of one einbodiment of my improved bit,showing it in position for drilling a hole for receiving the wellcasing; Fig. 2 is a view similar to Fig. 1, with the bit contracted aswhen it is withdrawn from and inserted into the ,well casing, and Fig. 3is a cross-section of the tool on the line 3 3 of Fig. 1, looking in thedirection ofthe arrows.

The tool is preferably entirely constructed of steel and is composed ofa body having a longitudinal central wedge-shaped slot eX- tending aconsiderable portion of its length and dividing it into side members 5,eachvof which is provided at its lower extremity with a double cuttingedge 6. Received between the members 5 within the slot of the body ofthe bit is a wedgeshaped member 7 having a corresponding cutting edge6a, and adapted to expand the side members 5 and bring the `cutting edge6a into substantial register with the cutting edges 6 when the wedge isforced to the top of the slot, as shown in Fig. 1.

As best shown in Fig. 3, the body of the tool is of rounding form withflattened sides, each side being provided at one edge with a rib 8 whichis arranged diagonally oppositel the rib of the opposite side. The sidemembers 5 of the body are also connected together at both sides neartheir cutting edges by overlapping projections or plates 9, one of whichis transversely slotted and the other carrying an engaging pin 11 whichacts as a stop to prevent the further separation of the members 5 whenthe wedge 7 is forced to the top of the slot between them. These platesor projections 9 are made as an integral part with their respectivemembers 5, as are also plates or projections 12 provided on the oppositesides of the wedge member 7 near its smaller end. These last-namedplates or projections, in connection with the plates 9, not only serveto guide the wedge and prevent any lateral displacement thereof, butalso operate as a stop, as shown in Fig. 2, to to prevent the completeseparation of the wedge from the body of the bit when the latter iscontracted. The wedge member 7 is constructed with grooves 13 atopposite sides for the discharge of the cuttings, and are provided abovethe projections 12 with pivotally suspended dogs 14, the said dogs beingsubstantially L-shaped arranged at opposite sides of the tool andserveto engage with the bottom edge of the well casing when withdrawingthe bit therefrom. This engageinent of the dogs with the casing, as thebit is withdrawn from the well, forces the wedge member downwardly withrespect to the side .members until the projections 12 encounter theprojections or plates 9, at which time the dogs swing out of the path ofthe casing and permit of the casing passing thereover. This is madepossible by providing the inner edges of the ribs 8, against which theback of the dogs bear, with rabbeted portions 15 which are of sufficientextent to permit of the dogs moving within the outline of the tool,whereby they may readily pass through the casing. The sh'ank of the toolis preferably constructed with a' threaded neck 16, as shown in dottedoutline in Fig, 1, for attaching it to the drill rod, and is furtherprovided with an angular portion 17 for removing and applying the bit tothe drill rod with a wrench.

The construction of the bit as above outlined and shown in theaccompanying drawings while being the preferred form of my invention,may obviously be modi'hed in numerous minor artieulars within the scopeof the annexed c aims.

Having thus described my invention, I claim as new and desire to secureby Letters Patent:

l. An expansion bit comprising a body having a tapering openingsubstantially longitudinally arranged and dividing the body into twoside members which are provlded with cutting edges, and a taperingcentral member fitting within said opening and having a cutting edgeadapted to register with the cutting edges of said side members.

2. An expansion bit comprising a body having a longitudinal slotdividing it into two side members which are provided with cutting edges,and a wedge member iitting inlto said slot and provided with a cuttingec ge.

3. An expansion bit comprising a body having a longitudinal slotdividing it into two side members provided with cutting edges, a wedgemember arranged within said slot adapted to expand the side members andprovided with a cutting edge, and dogs pivotally sus ended from thewedge member for withdrawing it from the side members.

4. An expansion bit comprising a body having a longitudinal wedge-shapedslot dividing it into two side members and pron vided with cuttingedges, a wedge member within said slot adapted to expand the sidemembers and having a cutting edge, and means for positively preventingthe further separation of said side members when fully expanded by thesaid wedge member.

5. An expansion bit comprising a body having a longitudinal wedge-shapedslot dividing it into two side members, a wedge member fitting withinsaid slot adapted to expand the side members, means for positivelypreventing the further separation of the side members when fullyexpanded by the wedge member, and means coacting with the last-namedmeans for preventing the complete removalof the wedge member frombetween the side members.

6. An expansion bit comprising a body having ribs arrangedlongitudinally at diagonally opposite edges and provided with awedge-shaped slot dividing it into two side members, a wedge memberfitting within said slot adapted to expand the side members, and dogspivotally suspended on the wedge member and adapted to bear against saidribs for the purpose described.

7. An expansion bit comprising a body having a longitudinal wedge-shapedslot dividing it into two side members provided with cutting edges, awedge member fitting into said slot adapted to expand the side membersand provided with a cutting edge, ribs formed on the side members havingrabbeted portions, and dogs pivotally suspended on the wedge memberadapted to bear against said ribs and pass into the rabbeted portionsthereof when the wedge member is withdrawn.

8. An expansion bit comprising a body having a longitudinal wedge-shapedslot dividing it into two side members, a Wedge member within the slotadapted to expand the side members, means connecting the side memberstogether operating to positively prevent the further separation thereofwhen the side members are fully expanded by the wedge member, meanscarried by the wedge member coacting with said last-named means toprovide a stop for preventing the complete withdrawal of the wedgemember from the side members, a rib longitudinally formed on one of theside members having a rabbeted portion, a dog pivotally suspended on thewedge member adapted to bear against said rib and pass into the rabbetedportion thereof when the iirst and last-named means contact.

In testimony whereoi1 l have signed my name to this specification in thepresence of two subscribing witnesses.

CHARLES AUGUSTUS BUTLER.

